Electrical recording device



June 23, 1942. A BLUE 2,287,463

ELECTRICAL RECORDING DEVICE Filed Jan. 17, 1940 Patented June 23, 1942 UNITED STATES PTENT QFFIQE ELECTRICAL RECORDING DEVICE Archie Henry Blue, Christchurch, New Zealand, assignor of one-fourth to Ross Derisley Wood, and two-twentieths to Henry Poynton Bridge, both of Christchurch, New Zealand Application January 17, 1940, Serial No. 314,328

2 Claims. (Cl. 12'6122) When applying the arrangement described to the recording of sound, electrical oscillations from a microphone are impressed, after suitable amplification on the anode 3 and filament 2. This brings the tube into such a state that a smallchange of current strength produces a large change in the light emitted in a direction axially of the anode in accordance with a linear relation. When adjusted in this way, the oscillatory varied in accordance with sound and the intencurrents on filament 2 and anode 3 cause the insity of the light emitted by the tube has been contensity of the light emitted to vary correspondtrolled in this way. ingly. These variations in light intensity may According to the present invention light modube used in known manner to produce a photolated in intensit in accordance with electrical graphic sound record- The light is o ou se or mechanical oscillations is generated by means emitted in a direction axially of the anode 3 and of a glow discharge tube, the light from which is in the form f a cyl n ri al l mn f li ht is electrically controlled or influenced. extending as far a h Wa Of the glass 0 The invention further provides a glow dlstainer envelopecharge device comprising an envelope containing In the circuit of Fig e 4 i tead o app y n mercury vapour and having disposed therein a vary Currents t0 fi nt Z d anode 3, the filamentary cathode, and an anode surrounding ligh v ri are obtained by imp n l said cathode, and a target grid arranged near trical oscillations upon target grid 4 and anode 3. the anode; said target grid is placed at the end, T e a et grid 4 i Connected to a p iv 1 0- so as to lie substantially along the axis of said tential in relation to anode 3. Electrical oscillafilamentary cathode, tion which may be derived as before from a The invention is illustrated by way of example microphone are impressed p the p y in the accompanying drawing in which Figures 1 Winding of the transformer 5 and in this way an and 2 show views in part sectional side elevation alternating petential difference is pp beand in end elevation respectively of a discharge tween electrodes 3 d Target d 4 is catube in accordance with the invention, and Figp y Coupled to Secondary 0f transfOrIner 5 ures 3 and 4 illustrate diagrammatically two cirby eapacitator 6, and in this way modulates the cuit arrangements according to the invention. light emitted- Referring to Figures 1 and 2, an envelope l Although the invention has been described which may be of quartz or glass is filled with with particular reference to sound recording, it mercury vapour at a suitable pressure. Within y be pp to Other P p s. W en for eX- the envelope 1 are mounted a filamentary cathample the ppa is used for transmitting ode 2 of helical shape and a cylindrical an d oscillations with the aid of light from one station 3 (for example of nickel) surrounding the cathto another the light from the sending station ode 2 may be allowed to fall upon a photosensitive de- Near one end of cylindrical anode 3 is placed Vice at the receiving a a target grid i. The filament 2 faces target grid The apparatus may he also U ed in Connection 4 through cylindrical anode 3. In this way when With the ece v station a phototelegraphie current is applied 130 filament 2 and target, grid 4 system, the incoming electrical oscillations being an electrical field is established in the discharge impressed p n the discharge vi n p oducspace around the filament 2 and parallel to the s rr sp ndi changes n t in nsity of the cylindrical anode 3. The effect of this electrical light emitted- In omb nat on with a suitable field is greatly to intensify the light emitted and an v therefore, t ap ar t m y to concentrate it in an axial direction. he used to build up at the receiving station the Referring to Figure 3, in which like parts are p u e ra smitted. given the same references as in Figure 1, the Having now particularly described and ascertarget grid 4 is connected to a point of positive a ied t e nature of my said invention and in potential relating to the cathode 2. The po- What manner the same is to be performed, I detential difference between the target grid 4 and clare that what I claim is: the cathode 2 may for example be about 250 1. A glow discharge device, comprising an Voltselongated envelope containing mercury vapor,

a filamentary cathode within and on the longitudinal center of the envelope, an anode in the form of a cylinder coaxial with the envelope and enclosing said cathode and electrically separated therefrom and having a terminal exposed exteriorly of the envelope for the connection of a source of electric potential therewith, and a target grid disposed in spaced relation with the cathode and spaced from an end of the anode and upon the axial center of the anode in line longitudinally of the anode with the cathode.

2. A glow lamp, comprising an elongated cylindrical tube, a filamentary cathode within the tube and disposed upon the longitudinal center thereof, an anode in the form of a cylinder extending lengthwise within and coaxial of the tube and enclosing said cathode and electrically separated therefrom, the anode having a terminal exposed exteriorly of the tube for connection Withasource of electric potential and the cathode having terminals exposed exteriorly of the tube for connection with said source, an annular target grid disposed in an end of the tube in spaced relation with the adjacent end of the cylindrical anode and coaxial therewith, said grid having a terminal exposed exteriorly of the tube, and a quantity of mercury within the tube for vaporization by said cathode when the latter is energized.

ARCHIE HENRY BLUE. 

